Thiol-terminated sulfur-containing polymers are known to be well-suited for use in aerospace sealants due to their fuel resistant nature upon crosslinking. Among the commercially available polymeric materials that have sufficient sulfur content to exhibit this desirable property are the polysulfide polymers described, for example, in U.S. Pat. No. 2,466,963, and the alkyl side chain-containing polythioether polymers described, for example, in U.S. Pat. No. 4,366,307. Materials useful in this context also have the desirable property of liquidity at room temperature.
Another desirable combination of properties for aerospace sealants that is much more difficult to obtain is the combination of long application time or “pot life” (the time during which the sealant remains usable) and short curing time (the time required to reach a predetermined strength). High temperature resistance may also be desired for aerospace sealants. Compositions that have low Tg, are liquid at room temperature, have good pot life and/or good performance characteristics are desired for aerospace applications.